Joseph Camarda

Coronary Artery Abnormalities and Sudden Cardiac Death

Anomalous origin of a coronary artery (AOCA) can be associated with sudden cardiac death (SCD), particularly in young athletes. The diagnosis usually can be made by transthoracic echocardiography. In the case of patients for whom this method is not diagnostic, other methods are available including transesophageal echocardiography, cardiac magnetic resonance imaging (CMRI), and computed tomographic (CT) angiography. The decision to intervene is dependent on the type of lesion, the course of the coronary artery, its known association with SCD, and any symptoms present at the time of diagnosis. For patients without symptoms who have lesions less clearly associated with SCD [e.g., anomalous origin of the right coronary artery (AORCA)], the decision to intervene is more controversial. Further prospective studies hopefully will elucidate the optimum treatment pathway for such patients.

MRI validated echocardiographic technique to measure total cardiac volume: a tool for donor-recipient size matching in pediatric heart transplantation.

Our aim is to develop and validate an accurate method for estimating TCV using standard echocardiographic imaging that can be easily employed to aid in donor–recipient size matching in pediatric heart transplantation. Thirty patients who underwent Echo and cardiac magnetic resonance imaging (cMRI) were identified. TCV was measured on cMRI. TCV was determined echocardiographically by two methods: a volume measurement using the modified Simpsons method on a four‐chamber view of the heart; and a calculated volume measurement which assumed a true‐elliptical shape of the heart. These two methods where compared with the value obtained by cMRI using the concordance correlation coefficient (CCC). TCV by method 1 correlated well with cMRI (CCC = 0.98%, CI = 0.97, 0.99). TCV by method 2 had a CCC = 0.90 (CI = 0.9464, 0.9716) when compared to cMRI. Left ventricular end‐diastolic volume (LVEDV) also correlated as a predictor of TCV in patients with structurally normal hearts and could be described by the equation: TCV = 6.6 (LVEDV) + 12 (R2 = 0.97). Echocardiographic assessment of TCV for recipients and their potential donors is a simple process and can be prospectively applied as part of donor evaluation.

Relationship of Echocardiographic Z Scores Adjusted for Body Surface Area to Age, Sex, Race, and EthnicityCLINICAL PERSPECTIVE: The Pediatric Heart Network Normal Echocardiogram Database

Background— Published nomograms of pediatric echocardiographic measurements are limited by insufficient sample size to assess the effects of age, sex, race, and ethnicity. Variable methodologies have resulted in a wide range of Z scores for a single measurement. This multicenter study sought to determine Z scores for common measurements adjusted for body surface area (BSA) and stratified by age, sex, race, and ethnicity. Methods and Results— Data collected from healthy nonobese children ⩽18 years of age at 19 centers with a normal echocardiogram included age, sex, race, ethnicity, height, weight, echocardiographic images, and measurements performed at the Core Laboratory. Z score models involved indexed parameters (X/BSA&agr;) that were normally distributed without residual dependence on BSA. The models were tested for the effects of age, sex, race, and ethnicity. Raw measurements from models with and without these effects were compared, and <5% difference was considered clinically insignificant because interobserver variability for echocardiographic measurements are reported as ≥5% difference. Of the 3566 subjects, 90% had measurable images. Appropriate BSA transformations (BSA&agr;) were selected for each measurement. Multivariable regression revealed statistically significant effects by age, sex, race, and ethnicity for all outcomes, but all effects were clinically insignificant based on comparisons of models with and without the effects, resulting in Z scores independent of age, sex, race, and ethnicity for each measurement. Conclusions— Echocardiographic Z scores based on BSA were derived from a large, diverse, and healthy North American population. Age, sex, race, and ethnicity have small effects on the Z scores that are statistically significant but not clinically important.

Co-registered MR tissue phase mapping and speckle tracking echocardiography: inter-modality comparison of regional myocardial velocities in pediatric patients

Background MR tissue phase mapping (TPM) enables assessment of regional myocardial velocities. The purpose of this study was to compare regional myocardial velocities obtained by both TPM and speckle tracking echocardiography (STE) to assess agreement and potential systematic differences between modalities. Methods

Biophysical properties of the aorta in patients with Marfan syndrome and related connective tissue disorders: evaluation with MRI and computational fluid dynamics modeling.

Objective The purpose of this study was to evaluate the biophysical properties of the aorta in patients with Marfan Syndrome or Loeys-Dietz Syndrome using MRI and computational fluid dynamics (CFD) modeling. Background Patients with Marfan Syndrome and related disorders have abnormal wall properties throughout the thoracic aorta including low distensibility in areas that eventually dilate. CFD modeling based on MRI data can be used to quantify distensibility and indices such as velocity and wall shear stress (WSS) throughout the cardiac cycle and for the entire thoracic aorta. We sought to use cardiac MRI and CFD modeling to evaluate the distensibility and indices of WSS in the aorta of patients with Marfan Syndrome and related disorders compared to age- and gender-matched controls. Methods Patients with Marfan Syndrome or a related disorder and no history of surgery who underwent a recent MRI were identified (n=6; 5 Marfan, 1 Loeys-Dietz). After measuring blood pressure, aortic wall dimensions and distensibility were calculated off-line by two independent observers at 3 locations: ascending aorta (AAo), thoracic descending aorta (DAoT), and descending aorta at the level of the diaphragm (DAoD). CFD simulations were performed using a stabilized finite element solver and incorporated downstream vascular resistance and compliance CFD models to quantify time-averaged WSS (TAWSS) and oscillatory shear index (OSI) throughout the aorta. Results

Persistent Fifth Aortic Arch: Echocardiographic Diagnosis of a Persistent Fifth Aortic Arch

(Echocardiography 2011;28:E44‐E45)

Practice Variations in Pediatric Echocardiography Laboratories

Quantification guidelines for pediatric echocardiograms were published in 2010 establishing consensus regarding standard measurements. However, a standard protocol for performance and analysis of pediatric echocardiograms was not defined. This study aims to identify practice variations among pediatric laboratories. A survey was sent to 85 North American pediatric laboratory directors. The survey included 29 questions assessing: demographics, methods of image acquisition, parameters routinely evaluated and reported, and methods used to assess chamber sizes, valves, and ventricular function. There were 47/85 (55%) responses; 83% were academic centers and 77% in an urban setting. Wide variations exist in acquisition method (clips versus sweeps) and color scale settings. The most commonly used methods for left ventricular (LV) function are M-mode shortening fraction, qualitative assessment, and Doppler Tissue Imaging. The most commonly used parameter for right ventricular function is qualitative. LV mass is routinely measured by the majority of centers with variations in methods of calculation. Conversely, while a minority measure left atrial volume, there is consensus regarding the preferred method. While multiple techniques exist for assessing valves, qualitative assessment is reported to be the preferred method. Despite quantification guidelines, there is a lack of uniformity in performance and analysis of pediatric echocardiograms. Further studies are needed to determine why variations exist and whether development of consensus guidelines might improve interpretation, consistency and quality of reports, patient care, and provide a standardized system allowing for comparative research among centers.

Prenatal diagnosis of the rare association of common arterial trunk and double aortic arch

Common arterial trunk with associated double aortic arch is a very rare constellation of congenital heart disease. Prenatal diagnosis allows for surgical repair prior to development of respiratory morbidity, which is otherwise described in all cases with this association.